They are typographically the right thing to have been using all along.
Using ' and " to pretend to be ‘/’ or “/” is on par with the typewriter days where people would use the l key to stand in for 1 also. A justifiable approximation when technology limitations prevented using the real deal, but an approximation all the same.
Can't that be handled by the typesetting/rendering software and displayed appropriately regardless of which specific character was typed?
Except l has a specific meaning that isn't 1, while the entire purpose of ' and " is quoting (and apostrophe).
The equivalent of l for 1 is doing font-specific pseudo smart quotes with ` and '
In fact, if we had been using left and right quotes from the beginning in shells, most “quoting problems” go away, as they’re all inherently rooted in not being able to know what level of nesting a quote character is at.